<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://unpkg.com/vue"></script>
    <script>
        window.onload=function(){
            Vue.component('my-component', {
                template: '<div>A custom component!</div>'
            })
            new Vue({
                    el:"#example"
                    })
        }
    </script>
</head>
<body>
<div id="example">
<my-component>hello</my-component>
</div>
</body>
</html>